A 6 year old boy presents with progressive weakness in muscles, and difficulty in walking upstairs. He has difficulty in walking on his toes and has a waddling gait. Hyperophy of calf muscles in noted. His CPK levels are 10,000 IU. Which of the following is the most appropriate diagnosis -

Ans. is 'a' i.e., Duchenne muscular dystrophy Clinical features of DMD The age of onset is 2-5 years. Early development of the child is normal, the disease begins to manifest when the child stats walking. The child walks clumsily, has difficulty in climbing stairs and the gait is waddling. Hyperophy of calf muscle is a characteristic sign and is visible by the age of 4-5 years. This is called pseudohyperophy because it is not true hyperophy of muscles, instead the muscle is replaced by fat and connective tissues. Pelvic girdle involvement is very common and can be elicited by Gower's sign. There is characteristic involvement of the muscle Calf muscles Glutei Deltoid (All these muscles are hyperophied) Brachioradialis Tongue muscle Sternal head of pectoralis major ) spinatus Supra (These muscles are atrophied) Eventually all muscles are atrophied Intelligence is usually subnormal Patient die in the second decade of life because of respiratory failure or due to associated cardiomyopathy. Diagnosis of Duchenne's muscular dystrophy is made by ? Elevation of the enzymes of the muscle -4 creatinine phosphokinase. Histopathology demonstrates diffuse changes of degeneration and muscle fibres of varying size.